Mineral wool insulation



Dec. 14, 1937. 5 SHAVER 2,101,921

MINERAL WOOL INSULATION Filed April 2, 1937 2 Sheets-Sheet 1 l l M I 1011 u l Z611 I L J U v 660396 DJ/zauerr llll llllllllll Dec. 14, 1937.

G. D. SHAVER MINERAL WOOL INSULATION Filed April 2', v1957 2 Sheets-Sheet 2 Patented Dec. 14, 1937 UNITED STATES PATENT. OFFICE 3,101,921 MINERAL WOOL INSULATION George D. Shaver, Crown Point, Ind. Application April 2, 1937, Serial No. 134,668

' 7 Claims. -(c1. 92-56) by means of a suitable binding material. The

purpose in making the cylinder in sections is to permit it to be applied to pipes already in posl-- tion having their opposite ends secured in such a manner that it would be impossible to mount them with a solid cylinder. Ordinarily today these semicylindrical sections are formed by means of moulds and cores. Inasmuch as there are currently twelve sizes of pipe having outer diameters from one-half inch to six inches, in

elusive, and there are four commercial wall thicknesses for each size of pipe, it will be ap* preciated that it requires forty-eight sets of outside moulds and twelve interior mandrels to produce one piece of insulation of each commercial size pipe. In order to produce this insulationtin commercial quantities as many as 500 or 1000 sets of moulds of each size would probably be required since any one mould would remain in a dryer eight to twelve hours before emerging to be refilled. In addition to mould requirements of several thousand moulds, a number of dryer tunnels or ovens are required, and similarly a large number of rack cars for carrying the moulds through the dryers.

With the above desiderata in view, an important object of the present invention resides in the provision of a simplified and more economical method of preparing insulation of this type. An important feature which contributes to the accomplishment of the foregoing object resides in the provision of a continuous process for forming cylinders of mineral wool upon moving mandrels. 7

As hereinafter described, the novel process contemplates .the provision of a plurality of mandrels adapted to rotate about their own axes and to move bodily through an endless or rotary path. Suction is applied to the interior of the mandrels to initiate adhesion between mineral wool particles and the mandrels. In operation the mandrels are passed through a liquid bath having mineral wool particles immersed therein and by controlling the period of immersion, the size of the end flanges on the :manjdrels, and the consistency of the bath, the amount of material collected and the consequent density of the finished product are regulated. As the mandrels move through the bath a cylinder of mineral wool particles is formed upon each mandrel and thereafter the forms or mandrels emerge from the bath and pass successively through shaping; drying and discharge stations. At the first of these stations moulding pressure is applied to compact the cylinder and accurately dimension it. Thereafter as the mandrels continue through their circular path of movement the drying station or oven is passed through. After this station in the continuous process has been-accomplished each mandrel has mounted upon it a cylinder of insulating material of the desired dimension and thereafter the cylinder may be removed from the mandrel by severing a Wall of the cylinder either while the mandrel is still within the machine, or

alternatively, after the mandrel has been tem-- porarily removed from the machine.

From the foregoing it will beappreciated that the process of producing mineral wool insulation of cylindrical form has been greatly simplified and the number of moulds required to produce a full line of commercial sizes has been greatly reduced. It is necessary only t0 have a series of mandrels (relatively few in number of each size), the outer diameters of which correspond to the inner diameters of the commercial size insulation tubes. The wall thickness of the insulation cylinder is, of course, controlled, as already pointed out, by the period of immersion, the diameter of the end flanges, and the consistency of the bath.

Various additional features are accomplished through practice of the present invention, including that of forming the cylinder in spirally wound form of nearly concentric layers with the fibers predominating circumferentially and at right angles with the axis of the pipe, thereby affording better insulating value. The cylinder is more rigid than is generally obtainable and requires no protective covering other than canvastained. A featurewhich contributes to the accomplishment of this last mentioned result resides'in the fact that the suction applied to the interior of the mandrel during the cylinder forming operation operates to draw hot air through the body of the cylinder while the latter is in the oven, thereby rapidly obtaining a uniform production.

Other objects and features of ,the invention will become apparent from a reading of the following specification in the light of the accompanying drawings, in which Figure l is a top plan view, partly in section, showing the sequence of operation. The machine illustrated in this figure is laid out in straight lines for the sake of ease and clarity in the drawings, although as hereinafter pointed out and as diagrammatically shown in Figure 6,

it may be desirable to have the mandrels travel in a circular or rotary path.

Figure 2 is a view in front elevation of the apparatus shown in Figure 1;

Figure 3 is a view of the mandrel showing its connection to the machine;

Figure 4 is a detailed view in section of the mandrel and connection shown in Figure 3;

Figure 5 is a view in section taken along the lines 55 of Figure 4;

Figure dis a diagrammatic view of a rotary machine constructed in accordance with the present invention;

Figure 7 illustrates a method of removing the formed insulating cylinder from the mandrel; and

Figure 8 is a view of the insulating cylinder assembled with its customary wrapping.

As shown in the drawings, a plurality of horizontally extending frame members Ill and i2 are spaced apart from one another and carry brackets or bearings l4 within which are rotatably journaled tubular members l6. These latter members are connected at their inner extremities with flexible hose extensions i8 and at their outer extremities are joined by means of elbows and sections 22 with T's 24. As diagrammatically shown in Figure 6, the layout of the machine simulates a wheel with the supporting members l6 and the flexible hose connections i8 constituting the spokes of the wheel, said flexible connections having communication with the interior of the hub 26 of the wheel. Although this is a desirable and compact arrangement or design it is to be appreciated that the endless path through which the supporting members pass may be in the form of a circle, an ellipse or any other suitable configuration. Furthermore, although as illustrated in Figures 1, 2 and 6, the members are adapted to move in a horizontal plane, the invention contemplates their disposal in other planes. For example, an endless chain might be arranged to move in a vertical plane, thereby affording an upper and lower course, as will be referred to hereinafter.

Turning to Figure 4, it will be observed that each T 24 ispivotally or rotatably mounted upon a sleeve member 30, which latter member has a .gear 32 integrally formed at one extremity therejn'f. In order to prohibit longitudinal movement of the sleeve 36 within the T a plurality of locking rings 28, 28 are positioned at opposite extremities of the T and have binding engagement with the sleeve. This construction prevents the T from moving lengthwise but permits free ro- {tatable movement between the two. As illust-rated in Figure 3, the outer extremity of thesleeve 30 is provided with a bayonet joint comprising a sleeve 34 and a pin 36, the latter being carried by the mandrel 40.

As shown, the mandrel is in the form of a hollow tube having a perforated wall located between oppositely facing flanges 42 and 44.

From the description just given it will be understood that the mandrel may be readily ,removed. from the machine through operation of the bayonet joint 34, 36.- "It has already been pointed out that there are twelve sizes of pipe up to and including only six inches for which cylindrical insulation is designed and there are four commercial wall thicknesses for each size. In order that a single mandrel 46 may be employed for the purpose of making all four wall thicknesses for a size of pipe corresponding to the mandrel, the flanges 42 and 44 are removable and adapted to be interchanged with flanges of greater or lesser diameter in order that the desired thickness of wall may be obtained. Also it will be appreciated that by reason of thequick removabillty of the mandrel 40 from the machine, other mandrels of varying-diameters may be quickly substituted in order to produce the various commercial sizes of insulation. Referring back for a moment to Figure 2, there is illustrated a tank 46 positioned in the path of the mandrels provided with an inlet 48 and mechanical stirrers 50. A bath of mineral wool particles and liquid is introduced into the tank 46 through the inlet 48 and is agitated by means of the stirrers 5B.

As the radial supports IGand the mandrels 40 move along their circumferential course, the gears 32, carried by the sleeve 36, engage a cooperating rack 52 which extends circumferentially of the machine. Thus, as the arms move in their circular course, the gears 32, through engagement with the stationary rack bar 52, cause rotation to be imparted to the mandrels 40 and accordingly it will be seen that as the mandrels move in a circular path around the machine they rotate about their own axes at the same time.

In order to facilitate initial adherence between the mandrel and the mineral wool particles in the bath, suction is applied to the interior of each mandrel by means now to be described. The hub 26 of the machine is connected with a source of suction and has communication'with each mandrel through the flexible hoseconnections i8, the supporting members IS, the connecting members 22, the Ts 24 and the hollow mandrel 40. As the mandrels rotate, suction is constantly applied through the perforations or openings in the wall of the mandrels. In order to prevent the rock wool from passing through the openings in the wall, it isproposed to coat or cover the mandrel with a screen or mesh of sufficient fineness to prevent such occurrence.-

the mandrel and the end of the sleeve valve.

Thus, as a mandrel is placed in position the valve is caused to recede against the action of spring 62 until the openings 58 and 60 are in registry with one another. As long as the mandrel is in position the openings remain in registry, but when the mandrel is removed the spring 62 urges the valve to its seated position. A pin 64 carried by the sleeve valve 56 moves through a slot 64 formed in the sleeve and limits the movement that the spring 62 can impart to the sleeve valve.

Referring once more back to Figure 2, itwill,

be seen that the tank 46 has a sloping discharge table 10 which extends upwardly to ahorizontal platform 12 which may, for convenience, be referred to as a drying platform. As the matrices or mandrels 40 descend into the bath, the sucthickness is formed on the exterior of the man-' drel. Owing to the movement of the mandrel through the bath and the simultaneous rotation of the mandrel about its own axis, a cylinder of insulating material is developed that is of novel configuration. The fibers are intimately laid in nearly concentric, however, spiral layers, predominantly circumferentially and at right angles to the axis of the mandrel. This tendency of the mandrel to build up layers in spiral formation is also due to the fact that most of the wool particles are at the bottom of the bath so that each time the mandrel rotates about its axis the fibers are added mainly at the bottom part of the mandrel, thereby building the cylinder up in spiral form something like a roll of cloth. As the mandrels approach the discharge end of the bath they engage the sloping discharge table 10 and as they do so they move in a position beneath a moulding belt or former 14 which is mounted to travel over a plurality of vertically adjusted rolls i6, 18. As the mandrels ascend the sprockets 32 remain in engagement with the rack 52, causing continued rotation of the mandrel and the insulatingcylinder which has, by' this time, been formed upon the mandrel, the belt 14 engages the loosely formed cylinder, diagrammatically'indicated by the reference numeral '80 in Figure 2, and supplies moulding pressure to the cylinder to compact the wool particles, solidify, the cylinder and render it substantially uniform in cross-sectional dimensions. As the mandrel reaches the end of the sloping discharge platform 10 it passes from beneath the moulding belt 14 and enters a drying oven 82 which has hot air or gases circulated through it by means of a blower 84 and an outlet 86. The suction in the mandrel not only serves to initiate adherence between the wool particles in the bath, but additionally it functions to draw the hot air through the formed cylinder, there-' by quickly, thoroughly and uniformly drying the cylinder that has been formed. After the mandrels pass through the drying oven or furnace 82 they may be removed from the machine and placed within a cutter of the type illustrated in Figure '7, in which sloping side walls 85, 81'

receive the mandrel and cylinder, together with the flanges 42 and 44. Vertically arranged knives 88 and 90 are arranged to approach one another along the dotted line 92 of Figure? and sever the insulating cylinder into two parts 94 and 96 illustrated in Figure 8. This permits removal of the cylinder from the mandrel, although it is to be appreciated that the insulating cylinder may be removed without being severed in the manner described. For example, by removing the removable flange 44, the cylinder may be slipped lengthwise over the mandrel, in which event it will be removed in the form of a com-- plete cylinder. However, inasmuch as it is necessary to cut the cylinder in half to permit it to beapplied to pipes already installed, it will probably be desirable to divide the cylinder while it is on the mandrel. Furthermore, if desired, a

traveling knife may conveniently be mounted on the machine to perform this cutting operation without the necessity of removing the mandrel from its support. Such a knife would be similar in design to that illustrated in Figure 7, but as just mentioned, would be mounted upon the supports to travel with them orupon the machine frame at some convenient point to perform the cutting operation as each mandrel passes. After the two semi-cylinders 94 and 96 have been removed fromthe mandrel they are placed together in the manner shown in.Figure 8 and l a wrapping 98 of canvas or other suitable material is placed about them to maintain the two parts in assembled position until they are used,

this canvas jacket becoming the permanent covering for the installed insulation.

The process and machine have been illustrated and described herein in a desirable embodiment, although it is to be realized that various modifications in the design and construction of the machine and the parts thereof may be effected without constituting any departure from the scope of the invention as set forth in the claims hereunto appended.;For example, the function of the suction is primarily to initiate adherence between the wool particles and the material, and this same function may perhaps be obtained by wrapping the mandrel with perforated paper coated with a cementitious material and sprinkled with wool particles. Thus, if thefirst wool particles are caused to adhere to the material by adhesives, the subsequent building up of the cylinder maybe effected by reason of the'suction applied and the natural tenacity between the initial particles and those subsequently added.

Similarly as already pointed out, instead of moving in a horizontal plane the mandrels might move along a horizontal path over a sprocket downwardly, and then again horizontally in'reverse direction along a lower path, again upwardly and back'along the original path. "Inthis arrangement the endless chain would be disposed in a somewhat vertical plane, the drying oven could be upon the lower level and the liquid bath upon the upper level. However, all such adaptations are deemed intended within .the ordinary engineering ability of a person skilled in the art and fall within the scope of the appended claims. p

Having thus described the invention, what I claim as new and desire to secure by Letters Patent of the United States is:

' I. That improvement in processes of forming mineral wool insulation in cylindrical form, which includes the steps of rotating a foraminous mandrel about an axis extending therethrough in a bath containing particles of such wool and 'ap said wool particles, moving said mandrel in a direction normal to its axis of rotation, and applying moldingpressure upon the wool particles collected toform a firm cylinder of substantially uniform cross-section. p

3. That improvement in processes of forming mineral wool insulation in cylindrical form,

which includes the steps or rotating 9. foramfnous mandrel about an axis extending therethrough in' a bath containing particles of such wool and applying suction to the interior of said mandrel to initiate tenacity ,between said mandrel. and said wool particles, moving saidmandrel -in a direction normal to its axis of rotation, and ap plying heat to the wool particles collected.-

4. That improvement in processes of forming mineral wool', insulation in cylindrical form, which includes the steps of rotating a ioraminous mandrel about an axis extending therethrough in a bath containing particles of such wool and applying suction to the interior of said mandrel to initiate tenacity between said mandrel and said wool particles, moving said mandrel in a for applying suction to the interior of said mandrels, and means for revolving said mandrels in said bearings whdreby the mandrels are im-,

mersed and then removed from the vat afteraccumulating fibrous material thereon.

6. In a machine of the class described, a vat adapted to contain a suspension of fibrous material; a plurality of hollow foraminous mandrels rotatable about their individual axes and supported in bearings carried by a conveyor movable along a path adjacent to and through said vat, means for applying suction to the interior of said mandrels, means for revolving said mandrels in said bearings whereby the mandrels are immersed and then removed from the vat after accumulating fibrous material thereon, and means in the path of the mandrels for compressing fibrous material adhering aroundthe mandrels.

7. In amachir'ie of the class described, a vat adapted to contain a suspension of fibrous material, a plurality of hollow foraminous mandrels rotatable about their individual'axes and supported in bearings carried by a conveyor movable along a 'path adjacent to and through said vat, means for applying suction to the interior of said mandrels, means for revolving said mandrels in said bearings whereby the mandrels are immersed and then removed from the vat after accumulating fibrous material thereon,'and heat-' 

